sci.physics.particle

On Mar 24, 12:19 pm, kenseto wrote:
> On Mar 24, 9:50 am, PD wrote:
>
>
>
> > On Mar 24, 9:44 am, "kens...@erinet.com" wrote:
>
> > > On Mar 20, 10:50 am, PD wrote:
>
> > > > On Mar 20, 9:21 am, "Androcles" wrote:
>
> > > > > "PD" wrote in message
>
> > > > >news:4c53fc2e-bcfd-425d-a7ed-afb8933257d2@e60g2000hsh.googlegroups.com...
> > > > > On Mar 20, 3:02 am, Pentcho Valev wrote:
>
> > > > > > On Mar 18, 7:29 pm, Tom Roberts wrote in
> > > > > > sci.physics.relativity:
>
> > > > > > > John C. Polasek wrote:
> > > > > > > > On Sun, 16 Mar 2008 17:14:22 GMT,TomRoberts
> > > > > > > > wrote:
> > > > > > > >> [Ignore Valev when he brings up Pound-Rebka and similar
> > > > > > > >> experiments -- they do not measure speed.]
> > > > > > > > I think, in a very important way, the experiment did effectively
> > > > > > > > measure light speed, even though the authors thought frequency was
> > > > > > > > reduced on the way up ("On the Weight of Photons" iirc).
> > > > > > > > The Mossbauer filter on a speaker cone was oscillated at a minute
> > > > > > > > rate, and spectral re-centering was achieved by the Doppler effect. On
> > > > > > > > the up-stroke, the velocity neutralized the speedup of light as it
> > > > > > > > left the gravity well.
>
> > > > > > > Think about it -- there is no time synchornization, and if the effect
> > > > > > > were due to a change in speed there's no way for the apparatus to be
> > > > > > > sensitive to it; that is, there's no "nominal distance" relative to
> > > > > > > which a "speed change" could be measured. Their observations are
> > > > > > > consistent with a change in frequency (measured via Doppler), and say
> > > > > > > nothing at all about any change in speed. Whether or not the speed
> > > > > > > changed in addition to the frequency cannot be answered by this
> > > > > > > particular experiment.
>
> > > > > > I would agree with you Roberts Roberts if at this place you did not
> > > > > > always stick your head in the sand, expose other parts of your body
> > > > > > and fail to explain clearly the two incompatible implications of Pound-
> > > > > > Rebka result f'=f(1+V/c^2). Let me do this for you:
>
> > > > > > The Pound-Rebka result f'=f(1+V/c^2) implies that:
>
> > > > > > (1) the speed of light in a gravitational filed is VARIABLE as
> > > > > > Einstein suggests in his 1920 "Relativity" and obeys Einstein's 1911
> > > > > > equation c'=c(1+V/c^2), whereas the wavelength remains constant. The
> > > > > > application of Einstein's equivalence principle converts c'=c(1+V/c^2)
> > > > > > into c'=c+v, an equation given by Newton's emission theory of light,
> > > > > > where v is the relative speed of the light source and the observer in
> > > > > > the absence of a gravitational field. Einstein's 1905 light postulate
> > > > > > (c'=c) is false.
>
> > > > > > (2) the speed of light in a gravitational field is CONSTANT and obeys
> > > > > > the equation c'=c, in contradiction to what Einstein claims in his
> > > > > > 1920 "Relativity". The wavelength is variable and obeys the equation
> > > > > > L'=L/(1+V/c^2). The application of Einstein's equivalence principle
> > > > > > leads to the conclusion that the equation c'=c+v given by Newton's
> > > > > > emission theory of light is wrong whereas Einstein's 1905 light
> > > > > > postulate (c'=c) is correct.
>
> > > > > > This is a minimum explanation Roberts Roberts - more could be said in
> > > > > > favour of (1) and against (2).
>
> > > > > | The above is incorrect in a number of ways.
> > > > > | 1. The Pound-Rebka experiment in no way implies that the wavelength is
> > > > > | constant. In fact, the opposite is true.
>
> > > > > What does it imply, then, now that we know what it doesn't imply?
>
> > > > It implies that the frequency and wavelength are shifted and the local
> > > > speed of light remains c.
>
> > > No..... it implies that frequency is shifted and wavelength remains
> > > constant
>
> > Why would it imply something that is counter to measurement?
> > Measurement shows that the wavelength is clearly shifted, as well as
> > the frequency.
>
> The wavelength of a specific source such as the sodium is universal as
> measured by all obserers. There is nothing during the transit of light
> can change that. The incoming light becomes a new light source in the
> observer's frame and the newly measured wavelength is the defined
> wavelength for this new light source.
>
> The speed incoming can indeed be affected by the individaul motion of
> the source or the observer. Therefore the observed freuqency shift is
> due to different arrival speed of the incoming light.
There is no way the grating, the telescope, or the aperture can
know that the light came from a sodium atom. The grating is too far
away for the light to remember the atom it came from. There is no
"universal wavelength." The source of the light can never be
universal, because once the light has left the atom it is on its own.
Therefore, both wavelength and frequency are affected by the velocity
of the grating, but in opposite directions. The product of these
quantities is the same velocity of light in a vacuum, which is
unchanged.
Another way to think of it is to consider the sodium atom as a
little, bitty antennae. There is something called the near field
approximation. Within a certain distance of the sodium atom, the
electromagnetic disturbance is affected by the sodium atom. The
disturbance is not a true wave. In a sense, the light is not in a
vacuum within a certain distance. Look up Jackson, Electrodynamics for
an explanation of near field approximation. The nearfield "wave"
remembers it is near a sodium atom within a certain distance. However,
the wave "forgets" the sodium atom by the time it reaches the grating.
So the local speed of light is unchanged.
Now for quantum mechanics. Within a certain distance, the
electromagnetic field consists of a mixture of "real photons" and
"virtual photons." Within a certain distance, the photon "remembers it
came from the sodium atom. However, at a certain distance the virtual
photons disappear. So only "real" photons hit the grating. They don't
remember having been emitted by a sodium atom. So the local speed of
light is unchanged.
Did you go to Erasmus Hall High School? I may know you.

>
>
>
> > > thus the speed of light is shifted to c'.
>
> > Multiplying the *measured* frequency with the *measured* wavelength
> > gives c, not c'.
>
> c'= (universal wavelength of the incoming light)(measured incoming
> frequency).
>
> Ken Seto